Malware-free describes an attack or alert where defenders do not find a traditional malicious file, payload, or implant. Instead of dropping obvious malware, attackers may use valid credentials, built-in admin tools, scripts, remote services, or cloud and identity features that already exist in the environment. This is often called a “living off the land” style of intrusion.
This matters because signature-based antivirus and many file-focused detections may never trigger. In malware-free incidents, security teams have to judge whether logins, process activity, API calls, or SaaS actions are normal or hostile. Effective defense depends on identity telemetry, behavior analytics, baselines, and context such as location, device health, privilege changes, and unusual lateral movement. It is common in cloud compromise, account takeover, and hands-on-keyboard attacks where the attacker tries to blend in rather than install malware.